2023年全國碩士研究生考試考研英語一試題真題(含答案詳解+作文范文)_第1頁
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1、<p><b>  附錄</b></p><p>  Plant Protection</p><p><b>  Abstract </b></p><p>  The cards on the upper surface were blue, says [John Howell]. In many cases

2、, cards on the lower leaves were not covered as well. "If growers want to check out coverage in any kind of crop, they can get these cards from machinery dealers," says Howell. "It is a great way to determ

3、ine what kind of spray coverage you are getting. We tested all these sprayers at 4 miles an hour and 2 miles an hour and we did it with the different types of sprayers."</p><p>  OVER the years, disease

4、 pressure on pumpkins and winter squash, especially in the Northeast, has become more severe. More than 30 years ago, these crops were not typically sprayed with fungicides or insecticides because it simply wasn't ne

5、cessary. Disease and insect pressure wasn't that significant - back then.</p><p>  Fast forward to about 15 years ago, and things were beginning to change. According to John Howell, retired extension veg

6、etable specialist at the University of Massachusetts, as demand for these crops, especially pumpkins for Halloween, increased, so did production and the spread of plant disease, particularly black rot. The result was tha

7、t spraying became a necessity.</p><p>  "Growers didn't want to drive through their fields with a sprayer because they would squash a few squash, and pumpkins," says Howell. "We had to con

8、vince them that losing a few plants this way was better than losing much more to disease."</p><p>  Sprayer Vs. Sprayer</p><p>  According to Howell, most growers use high-pressure volume s

9、prayers to apply insecticides and fungicides to row crops. Some use air blast sprayers and low-volume units.</p><p>  From past research spraying insecticides and fungicides on pumpkins and squash, Howell le

10、arned that none of the sprayer types worked as well as they would have liked them to. Low-volume and air blast sprayers fell short in being able to successfully penetrate the canopy and achieve good leaf coverage.</p&

11、gt;<p>  Low-volume sprayers, says Howell, are typically used to spray herbicides directly on the soil, so applying product to plant leaves to prevent disease isn't the main goal. The air blast units, he learn

12、ed, had difficulty getting coverage under the plant canopy. Of the three types, the high-pressure volume sprayers provided the best coverage to plant leaves.</p><p>  "They all did a good job on the upp

13、er surfaces of the upper leaves," he explains. "However, you also want to be able to get the lower leaves that are lower in the canopy and the undersides of those leaves, as well. I think slowly more growers ar

14、e becoming more aware of this issue with spray coverage."</p><p>  During his research, Howell employed the use of water-sensitive cards. These yellow cards were clipped on the top upper leaves of plant

15、s and on leaves lower to the ground. Water was substituted for a crop protectant so researchers could walk through the fields after the plants were sprayed. Cards that got wet turned blue.</p><p>  The cards

16、 on the upper surface were blue, says Howell. In many cases, cards on the lower leaves were not covered as well. "If growers want to check out coverage in any kind of crop, they can get these cards from machinery de

17、alers," says Howell. "It is a great way to determine what kind of spray coverage you are getting. We tested all these sprayers at 4 miles an hour and 2 miles an hour and we did it with the different types of sp

18、rayers."</p><p>  Howell adds that spraying pumpkins and squash are particularly challenging, thanks to the amount of foliage that needs to be covered. Researchers also are using water-sensitive cards t

19、o test the coverage of fungicides and insecticides on other crops, such as sweet corn, he says.</p><p><b>  植物保護(hù)</b></p><p><b>  摘要</b></p><p>  在上表面的卡是藍(lán)色的,說

20、[約翰豪厄爾]。在許多情況下,在下部葉卡也沒有涉及。 “如果種植者想看看在任何一種作物的覆蓋面,他們可以從機(jī)械經(jīng)銷商那里得到卡片,“豪威爾說。 “確定你正在用什么樣方式來噴涂覆蓋面這是偉大的。我們?cè)?英里的時(shí)速和2英里的時(shí)速測試所有這些噴霧器,我們用不同類型的噴霧器來測試。</p><p>  通過確保你增加南瓜和西葫蘆作物涵蓋量,來增加作物保護(hù)劑的產(chǎn)量。</p><p>  多年來,尤其

21、是在東北,疾病對(duì)南瓜、冬瓜的壓力變得更加嚴(yán)重。30多年前,這些作物通常不噴灑殺菌劑或殺蟲劑,因?yàn)樗緵]有必要。病蟲害壓力并不顯著。當(dāng)時(shí)的情況??焖倩氐酱蠹s15年前,事情開始發(fā)生變化。據(jù)約翰豪威爾——一位退休的常識(shí)淵博的麻省理工大學(xué)的蔬菜專家,他認(rèn)為,隨著這些作物,尤其是萬圣節(jié)南瓜的需求的增加而加速了植物疾病的傳播,特別是黑腐病。其結(jié)果是,噴灑農(nóng)藥成為必然。 “種植者不希望駕駛一個(gè)攜帶噴霧器的機(jī)械駛過自己的田地,因?yàn)樗麄儠?huì)損失

22、幾個(gè)南瓜,”豪威爾說。 “我們必須說服他們,通過這種方式失去幾個(gè)南瓜,比被一些植物的疾病奪去更多的南瓜要好?!?不同噴霧器的比較 據(jù)豪威爾介紹,大部分種植者通過用高壓噴霧器噴灑殺蟲劑和殺菌劑來保護(hù)中耕作物。有的用鼓風(fēng)噴霧機(jī)和低容量噴霧器。 ,豪威爾了解到,從過去的南瓜和西葫蘆噴灑殺蟲劑和殺菌劑的研究來看,噴霧器類型沒有一次達(dá)到他們預(yù)期的效果。低容量噴霧器和鼓風(fēng)噴霧機(jī)沒有能夠成功地滲透,實(shí)現(xiàn)良好的葉冠層覆蓋。

23、 豪威爾說,低容量噴霧器通常用于在土壤上直接噴灑除草劑,使植物葉片應(yīng)用產(chǎn)品,以防止疾病,但不是主要目標(biāo)。他</p><p>  使用裝滿了水的高壓噴霧器,當(dāng)水滴落到上面的時(shí)候,這些黃水敏卡變成了藍(lán)色。是最高的卡嗎?是在每一列葉子的最頂面。第二張卡片是從上面葉子的下表面,第三卡是下面葉子的上表面,第四張卡在底面。這很難實(shí)現(xiàn)的葉片的良好覆蓋。 霍維爾補(bǔ)充說,由于大量的葉子覆蓋,噴涂南瓜和壁球特別具有挑戰(zhàn)性。研究

24、人員還使用水敏卡來測試殺菌、殺蟲劑劑在其他作物,如甜玉米,的覆蓋面。</p><p>  使用正確的噴嘴約翰豪威爾是一位退休的在馬薩諸塞大學(xué)的蔬菜推廣專家說,種植者應(yīng)該使用他們的南瓜和西葫蘆植株高壓噴霧器,他們應(yīng)該使用實(shí)心錐噴嘴。他說,大多數(shù)噴霧器使用空心錐噴嘴。 “一個(gè)實(shí)心錐角范圍較窄,而且往往難以把噴涂藥劑推入葉子?!彼f。他還告訴種植者不能在超過每小時(shí)2英里的速度時(shí)噴涂,因?yàn)樗枰獣r(shí)間來推入樹冠下的噴涂

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